FAA Lifts Nationwide Ground Stop After Telecom Outage Halts Flights Across U.S., Including Chicago

At O'Hare on Friday afternoon, travelers coming through security looked up at the departure screens and saw delays posted on nearly every line. That was how many of them learned the Federal Aviation Administration had stopped flights across the country. Some called friends and family to work out whether to spend the night in Chicago or find another way home.

The FAA lifted the nationwide ground stop shortly before 7:30 p.m. Friday, after it had halted flights for hours. It covered O'Hare and Midway in Chicago. The agency's notice said the order was issued "due to extraordinary circumstances and for reasons of safety." Transportation Secretary Sean Duffy said the agency was investigating a communication problem affecting 22 regional air traffic control centers, the facilities that direct planes traveling between airports. A few international flights still took off Friday evening from hubs on the East and West coasts.

Homeland Security Secretary Markwayne Mullin told reporters at the White House there was no indication so far that this was a nefarious attack, calling it a telecommunications outage "as of right now." He said there was no reason for people to worry about loved ones in the air, and that his office had found nothing tying the failure to a cyberattack. The last nationwide ground stop came in January 2023, when a key FAA computer system malfunctioned. Before that, the previous one followed the Sept. 11, 2001, attacks.

The numbers were large. By 5:50 p.m. Eastern, Cirium, an aviation analytics firm, counted at least 600 diverted flights: 496 returned to their departure airports and 104 went to different ones. O'Hare, Denver International, Dallas Fort Worth and Reagan National were among the airports receiving many of them. About 11,000 flights carrying more than 1.5 million passengers were scheduled to depart after 4 p.m. Eastern, which raised the likelihood of more cancellations and diversions. Multiple NBA, NHL and college teams were stranded, scrambling a busy sports weekend.

Passengers described the disruption in personal terms. Amber McQuilkin, a 27-year-old software engineer from Seattle, sat on a bench at O'Hare, worried she would miss a trip to New York for the League of Legends world finals. Her friends had already arrived, and she had taken a week of vacation. She said little information was reaching her, and that she had considered driving before concluding it would be miserable. Austin Curtis and his wife, traveling from South Bend, Indiana, to a friend's baby shower in Denver, had boarded their connecting flight at O'Hare when they were told to get off. They saw luggage being unloaded from their plane and others and expected a long delay. With care arranged for their two young children, he said, they might stay the weekend in Chicago and make the most of it. Jeff Dubner, a Washington, D.C., attorney, was on an Alaska Airlines flight from Los Angeles that was already half an hour late when it stopped while taxiing. He said it sounded like more than a routine delay.

Gov. JB Pritzker posted that the ground stop's impact on Illinois travelers needed to be addressed quickly while keeping safety paramount. He said state officials had no further information from DHS or the FAA but were in touch with them and demanding answers. SpaceX, meanwhile, launched its Starship rocket from Texas on Friday afternoon on a test flight.

No timeline for restarting flights was given while the stop was in effect. Mullin said investigators will examine whether the outage connects to the FAA's nationwide rollout of a new artificial intelligence system that helps spot problems and reroute planes, though that system runs from one location near Washington and only sends recommendations to the control centers. Congress approved $12.5 billion last year to modernize controller technology, and old copper wiring has been replaced with fiber optic lines while aging radio systems are gradually swapped out. Duffy has said $30 billion more is needed, and the White House has begun lobbying Congress for it.

Aviation safety expert Steve Arroyo, a former United Airlines pilot, said the problem resembled a September regional communication outage that snarled hundreds of Northeast flights, only on a national scale, and may relate to outdated equipment. If controllers cannot communicate, he said, planes must be kept on the ground. He added that Friday differed from the Sept. 11 stop because aircraft were not ordered to land immediately and pilots likely could still talk to airport ground controllers. The cause remains to be established.